Display screen or portion thereof with transitional graphical user interface



FIG. 1 is a front view of a first image in a sequence according to ourdesign for a display screen or portion thereof with transitionalgraphical user interface;

FIG. 2 is a front view of a second image in the sequence thereof; and,

FIG. 3 is a front view of a third image in the sequence thereof.

The appearance of the transitional image transitions between the imagesshown in FIGS. 1-3 . The process or period in which one imagetransitions to another forms no part of the claimed design.

The outer broken line rounded rectangles showing a device, the brokenline rectangle showing the display screen or portion thereof, and allother broken lines showing portions of the graphical user interface formno part of the claimed design.

CLAIM The ornamental design for a display screen or portion thereof withtransitional graphical user interface, as shown and described.